Sunday, March 18, 2012

A pixel, from Earth to the Moon, the infinite and beyond

“Usually when you see wacky space pictures, the Moon is unrealistically close to the Earth. What’s up with that? I wanted to get a better sense of exactly how the Earth and Moon would appear from an observer in space.” And that’s what Drew Olbrich did in the most beautiful image above. For all its emptiness, it’s beautiful for all it represents.
"This image has the most impact if you make it fill your whole screen and then turn off all the lights in the room" suggests Olbrich. "Stare at it for a while and try to imagine that you’re out in space looking back through some kind of bizarre porthole."
Click the on image to check the image in higher resolution versions. And speaking of higher resolution, while I was contemplating this image I started thinking of what would be the size of the Apollo spacecraft travelling the distance: 250,000 miles.
It would certainly be so tiny that it would not be visible, being less than a pixel in size. The obvious question then is: what should be the image’s minimum resolution to have the Apollo spacecraft appear as a single pixel?
Well, the command and service modules were about 11 meters high. The lunar module that landed in the Moon was about 6 meters high. Let’s be generous (and a bit arithmetically lazy) and consider the whole set as 20 meters in size. If they were represented as a single a pixel, then the 250,000 miles, or 400,000 km, that is, 400 million meters that separate the Earth from the Moon would occupy 20 million pixels.
If your computer screen has a 1024 pixels horizontal resolution and the distance from our planet to the Moon filled the screen in length, a single pixel in your screen would be around 20.000 wider than the size of the Apollo spacecraft.
Picture 20.000 spacecrafts one after the another to fill a single dot in your screen. It’s quite hard. In fact, that would be only in one dimension, so if we were to be lazy again and assume the Apollo spacecraft was much like a spherical cow, or rather, a square spacecraft 20×20 meters in size, then you would have 20.000×20.000 Apollo spacecrafts to really fill one single square pixel. That’s 400 million square Apollo spacecrafts arranged one next to the other like in a parking lot. Represented as a single dot. The real number is bigger than that, as the spacecrafts were obviously not square, but cylindrical, slender.
That’s quite hard to even imagine.
You can do the opposite instead, and picture a 20 million pixels horizontal resolution screen. That would be equivalent to 10,147 full HD TVs side by side. A 1024 pixels resolution would mean 10,531 PC monitors. If each were about 40 cm wide, that would make almost 4 km, over 2 miles of computer screens.
Amongst all these screens, running over a couple of miles, a single point, a tiny pixel would represent the Apollo spacecraft. Everything else would be empty space. A single dust particle could accidentally cover the pixel. One dead pixel could ruin the thing. And the three astronauts inside the shuttle would be even smaller. They would be still be smaller than a pixel even with miles of screens.
Now, picture yourself being inside this lone pixel.
"I am alone now, truly alone, and absolutely isolated from any known life." wrote Michael Collinswhile he was orbiting the Moon. Neil Armstrong and Buzz Aldrin were walking in our satellite for the first time in the epic history of these naked apes. Collins loneliness may not seem so great if you consider that, even though he was far from Earth, his two friends were "just" 65 miles away, which was the height at which he was orbiting the Moon.
But orbiting means circling the Moon. He was 65 miles away from his two friends only when he was directly above then. That was the closest he would be from the Apollo 11 landing site. For two revolutions, Collins went over the far side of the Moon, where not only he couldn’t see Amstrong or Aldrin, but communication with Earth was also impossible. Those were the moments he was "truly alone". The loneliest person ever.
Collins confided in his notes: "My secret terror for the last six months has been leaving them on the Moon and returning to Earth alone". Try to imagine being smaller than that pixel and having to go through two miles of screens. "Now I am within minutes of finding out the truth of the matter, if they fail to rise from the surface, or crash back into it, I am not going to commit suicide; I am coming home, forthwith, but I will be a marked man for life and I know it."
Dreary words that portray a little known story of the Apollo 11 journey as told by the "forgotten astronaut", detailed in an excellent article by Robin McKie at the Guardian.
Forty years later, we know nothing like that happened. Fortunately, all manned missions to the Moon had three passengers making company to each other.
Which reminds me of something else.
Right now we are more than 6 billion passengers of what Buckminster Fuller popularized as Spaceship Earth. We may not be that lonely, but all the company we have is each other’s. And whilst Earth would fill a lot of screens if each pixel represented 20 meters, our planet is not really that large. And it’s only one.
It would be impossible to end this post without mentioning that, as Apollo could be represented as a single pixel lost in the middle of thousands of screens, Earth itself can be seen as a pixel from the edge of the Solar Sysrem. It is a Pale Blue Dot.
Collins terror was not a sign of weakness but of the most reasonable sanity. Those are the thoughts we must all share when realizing how, in spite of the chances of life in the Solar System and alien civilizations in the Galaxy, as far as we know we are all "truly alone", "absolutely isolated from any known life" besides our own.
The abyss Collins stared at is the same one we have been staring from our Pale Blue Dot since the dawn of mankind. It took us a long time to realize that, and few have grasped just how deep it is.
Some may despair at the prospect. It’s only natural, as we are naked apes. But we are also intelligent apes. Isn’t it more than clear we must take care of our only, tiny pixel? And if the abyss stare back at us, must we not seek other pixels – going to the infinite and beyond, searching other lifeforms, "to boldly go where no man has gone before"?
Collins conquered the abyss and safely returned with his friends. Five other missions conquered 250,000 miles of distance, landed on the Moon and came back. Single pixels travelling for miles of screens. If we only try, we are capable of achievements so absurdly great that it’s difficult to even grasp their greatness.
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This whole exercise also makes it clear why you cannot take a picture of the artifacts left behind by the astronauts in the Moon: they are smaller than the smaller resolution unit even of the Hubble space telescope, orbiting Earth. Some recent images of these objects were only obtained by satellites in the Moon’s orbit.
Olbrich image also reminds of a 
slightly wet piece or rock.
The top image is from, the Earth-moon scale image was seen at Chongas, and Collins comments were seen in Fogonazos.
This is a version of the text originally published on 
Brazillion Thoughts.

Stolen from